TABLE 2.

Variables measured and summary of findings of the included studies.

Study	Functional measures and muscle soreness	Biochemical markers of muscle damage, inflammation and oxidative stress	Significant differences between Q and PLA groups
Nieman et al. [38]		IL-1ra, IL-6, IL-8, IL-10, MCP-1, TNF-α. Measurements: each day pre and post.	↓ IL-8 and TNF-α post the three days (tendency: p < 0.1)
McAnulty et al. [39]	-----------------	CRP F2-IsoP, FRAP, TEAC Measurements: each day pre and post.	No significant differences
Abbey & Rankin [40]	-----------------	IL-6 XO, UA Measurements: baseline, pre, post and 1 h post.	No significant differences
O’Fallon et al. [41]	MIVC of EF, MVC of EF at 60 and 180º/s, soreness, REA. Measurements: pre, post (only MVC and REA), 24 h, 48 h, 72, 96 h and 120 h post.	CK IL-6, CRP Measurements: pre and 24 h, 48 h, 72 h, 96 h and 120 h post.	No significant differences
Sholten & Sergeev [42]	-------------	MDA, PC, TAC, SOD Measurements: pre and post.	↓ PC, SOD, TAC post Significant differences between groups not really measured
Demirci [43]	-------------	MDA, SOD, CAT, GSH Measurements: baseline and post.	↑ SOD, CAT, GSH ↓ MDA Significant differences between groups not really measured
Duranti et al. [44]	-------------	GSSH, GSH/GSSH, TBARS Measurements: baseline, pre and post.	↓ GSSG post ↑ GSH/GSSG post ↓ TBARS post
Gholami & Ardestani [45]	-------------	TNF-α Lactate Measurements: baseline, pre and post.	↓ TNF-α post
Patrizio et al. [46]	MVIC of the KE, MVC of KE at 30, 90, 180 and 240º/s, RTD200, soreness. Measurements: baseline, pre and post.	CK GSSH, GSH/GSSH Measurements: baseline, pre, post and 24 h post.	↑ MVC at 30, 90, 180 and 240 º/s post ↓ loss of MVIC of KE post ↑ RTD200 post
Bazzucchi et al. [47]	MVIC of EF, MVC of EF at 30, 60, 120 and 240 º/s, soreness, REA. Measurements: baseline, pre and post.	CK, LDH Measurements: baseline, pre, post. 24 h, 48 h and 72 h post.	↑ Relaxed EA post, ↑ MVIC pre and post ↑ MVC at 30 and 60 º/s post ↓ Soreness post (tendency) ↓ CK 48 and 72 h post ↓ LDH 24, 48 and 72 h post
Bazzucchi et al. [48]	MVIC of EF, MVC of EF at 30, 60, 120 and 240 º/s, soreness, REA. Measurements: baseline, pre, post, 24 h, 48 h, 72 h. 96 h and 7 days post.	CK, LDH Measurements: baseline, pre and 48 h, 72 h, 96 h and 7 days post.	↑ Relaxed EA post, ↑ MVIC post, 24 h, 72 h and 96 h post ↑ MVC most velocities and time-points ↓ CK 72 and 96 h post ↓ LDH 48, 72 and 96 h post
Sgrò et al. [49]	MVIC of EF Measurements: pre and 24, 48 h, 72 h, 96 h and 7 days post.	CK, LDH, MB IL-6 Measurements: pre and 24, 48 h, 72 h, 96 h and 7 days post.	↑ MVIC in all recovery time points ↓ CK 72 and 96 h post ↓ LDH in all recovery time points ↓ MB 48, 72 and 96 h post ↓ IL-6 48 and 72 h post
Tsao et al. [50]	-------------	CK, MB IL-6, TNF-α, CRP Measurements: pre, post, 1 h and 24 h post. SOD, MDA, TAC. Measurements: pre, post and 1 h post.	↓ CK 24 h post ↓ IL-6 post and 1 h post ↑ TAC 1 h post ↑ SOD pre, post and 1 h post ↓ MDA post

MIVC: maximal isometric voluntary contraction; EF: elbow flexors; MVC: maximal voluntary contraction; RAA: relaxed elbow angle; KE: knee extensors; RTD200: isometric rate of torque development the first 200 ms; IL: interleukin; MCP-1: monocyte chemoattractant protein 1; TNF-α: tumor necrosis factor alpha; CRP: C-reactive protein; F2-IsoP: F2-Isoprostanes; FRAP: ferric reducing ability; TEAC: trolox equivalent antioxidant capacity; XO: xanthine oxidase; UA: uric acid; CK: creatine kinase; MDA: malondyaldehyde; PC: protein carbonyls; TAC: total antioxidant capacity; SOD: superoxide dismutase; CAT: catalase; GSH: reduced glutathione; GSSG: oxidized glutathione; GSH/GSSH: reduced to oxidized glutathione ratio; TBARS: thiobarbituric acid reactive substances; LDH: lactate dehydrogenase; MB: myoglobin.